Government regulations require utility companies to implement sufficient procedures to safeguard employees working underground on utility apparatus, for example, sewer, telephone, television, fuel, electric, or water lines, or some other utility apparatus requiring excavation of a hole for access thereto. In this regard, see 29 C.F.R. .sctn. 1926.650 et seq. (Occupational Health and Safety Administration, Labor). Generally, underground work on utility apparatus may be required when a utility apparatus is damaged in some way or when one utility apparatus is to be connected to another, for example, in the case where a main sewer line of a residential home is to be connected to a city sewer line in the street.
During the procedure, a primary concern is the collapse, or cave-in, of surrounding soil upon a worker while the worker is in the excavated hole. When the hole is excavated, the foregoing government regulations require a particular slope configuration, ranging from 34.degree. to 53.degree. from the horizontal., depending upon the soil composition surrounding the hole, and as the hole depth increases, a step configuration, often called a "benched excavation," is required in the slope configuration. Support or shield systems are also suggested in combination with some slope configurations. Generally, these support and shield systems include support structures and/or shores made of wood and/or steel beams.
However, the requisite safeguards in the industry as described above are very time consuming, labor intensive, oftentimes expensive, and impractical in many situations where the ground surface is cluttered with other structures or apparatus which cannot be readily moved or removed. Examples of immovable structures include a street, tree, or telephone pole. To make matters worse, the easement of the utility company is usually very limited so that excavation beyond certain limits is prohibited.
Thus, a heretofore unaddressed need exists in the industry for a novel process of permitting easy, inexpensive, and well protected access to an underground utility apparatus by a worker which does not suffer from the disadvantages and inadequacies of the prior art.